In recent years, there have been put to practical use automatic transmissions equipped with a shift-by-wire (SWB) mechanism that electrically switches the shift range of an automatic transmission by detecting with a switch or the like the shift range that the driver has selected, and driving an actuator of an electric motor or the like based on the detection result. Here, technology (a parking control device) is disclosed in Patent Literature 1 that, in an automatic transmission to which a shift-by-wire mechanism is applied, reduces the large noise and shift shock when releasing the parking state in a situation of a vehicle being parked at an incline.
In this parking control device, in a situation of a vehicle being stopped at an incline, in the case of the release of the parking state being requested by the shift lever being operated, based on the incline direction of the vehicle, the hydraulic pressure control device of the automatic transmission is switched to the forward travel state (D range) or the reverse travel state (R range), and after the forward travel state or reverse travel state is formed, the parking state (parking pole) is released. For that reason, according to this parking control device, prior to releasing the parking state, it is possible to apply torque in the forward travel direction or reverse travel direction so as to oppose the load due to the weight of the vehicle that occurs in the output shaft of the vehicle, and it is possible to smoothly release the parking state.